1. Field of the Invention
The present invention relates to a method of specimen analysis and a specimen analyzer analyzing a specimen such as plasma, serum or urine.
2. Description of the Background Art
In general, a specimen analyzer optically measuring the quantity and the degree of activity of a specific substance contained in a specimen such as plasma, serum or urine is known in the field of clinical tests. Such a specimen analyzer prepares an analytical sample by adding a reagent to the specimen, and thereafter applies a light of a prescribed wavelength to the analytical sample. A method of specimen analysis obtaining analytical results by analyzing scattered light or transmitted light from the analytical sample is generally employed.
In a specimen having symptoms of hemolysis, chyle or icterus, it may be difficult to perform correct optical measurement. This is for the following reason: When plasma is employed as the specimen, a hemolytic specimen is reddish due to a large quantity of hemoglobin contained in the specimen, although normal plasma is pale yellow and substantially transparent. Further, a chylous specimen is milky due to a large quantity of lipid contained in the specimen. In addition, an icteric specimen is yellow or yellow-green due to a large quantity of bilirubin contained in the specimen. Thus, when a substance (interfering substance) such as hemoglobin, lipid or bilirubin hindering the optical measurement is present in the specimen, a light of a specific wavelength is absorbed or a change rate of scattered light is insufficiently obtained, whereby it is difficult to perform correct optical measurement. Particularly in a case of a specimen exhibiting remarkable symptoms of hemolysis, chyle and icterus, it is more difficult to perform correct optical measurement.
In order to solve the aforementioned inconvenience, therefore, there is generally proposed a specimen test automation system automatically determining the state of a specimen before analyzing the specimen with the specimen analyzer. Such a specimen test automation system is disclosed in Japanese Patent Laying-Open No. 7-280814, for example. This disclosed in Japanese Patent Laying-Open No. 7-280814 has a dispenser dispensing a specimen from a specimen container and an automatic analyzer analyzing the specimen dispensed by the dispenser, for measuring presence/absence of hemolysis, chyle and icterus (interfering substances) in the specimen with a separately provided “hemolysis, chyle and icterus measuring apparatus” before analysis of a serous specimen with the automatic analyzer and collating the results of the measurement with requested test items for the automatic analyzer. The system so controls the automatic analyzer as to analyze only requested test items whose analytical results are not influenced by the interfering substances contained in the specimen and not to analyze requested test items whose analytical results are influenced by the interfering substances contained in the specimen on the basis of the results of the collation. If no requested test items analyzable in relation to the serous specimen are present as the result of collation, the system so controls the dispenser as not to dispense the serous specimen. Thus, the specimen test automation system according to the aforementioned Japanese Patent Laying-Open No. 7-280814 suppresses reduction of the analytical efficiency of the automatic analyzer.
The aforementioned Japanese Patent Laying-Open No. 7-280814 discloses a structure spectrally measuring the states of hemolysis, chyle and icterus from outside a blood collection tube. However, a bar code label for specifying the specimen is generally between blood collections, and this bar code label may be such a hindrance that it is not possible to correctly measure the interfering substances.
On the other hand, U.S. Pat. No. 6,797,518 discloses a structure measuring interfering substances with respect to a specimen remaining on the forward end of a measuring chip sucking the specimen, while U.S. Pat. No. 5,734,468 discloses a structure sucking a specimen with a probe having a needle and a transparent portion and measuring interfering substances with the transparent portion of this probe.